When you roll up a cigarette in public, you're almost guaranteed to get a funny look from one or two people who think you're rolling a joint. I've found this is a good way to meet people (even better than asking to use someone's lighter). The downside is that if you happen to have illegal substances in/on you, this attention could get you in trouble.

People are often impressed at your ability to roll a cigarette; especially if you can do it w/ one hand while talking on the phone :)

Rolled cigarettes are stronger, so you don't need to smoke as often to satisfy your nicotine quota (that's not to say that you won't smoke as often though).